Abrasive-containing element for multi-element abrasive tool, abrasive tool, and method for manufacturing the same

ABSTRACT

An abrasive-containing element has at least one pellet provided with an abrasive-containing layer and an abrasive-free layer, and at least one holding member having one end connected with the abrasive-free layer of the pellet and another opposite end introducible into a tool body for connecting the pellet to the tool body, and an abrasive tool has a plurality of such abrasive-containing elements connected to its tool body.

BACKGROUND OF THE INVENTION

The present invention relates to abrasive tools and method of manufacturing of the abrasive tools.

Abrasive tools, for example diamond tools, are known, which have a tool body and abrasive-containing pellets attached to the tool body. Each of the abrasive-containing pellets in the known abrasive-containing tools contains a plurality of abrasive grains connected with each other by a binder composed for example of a metal powder, a resin, etc. The abrasive-containing pellets are connected with the tool body by an adhesive layer.

The known abrasive-containing tools cited hereinabove have however disadvantages in that the connection of the abrasive-containing pellets to the tool body is not sufficiently strong to execute the processes of machining of corresponding parts with high pressures and high speeds, since the machining with these high parameters results in detaching of the abrasive-containing pellets from the tool body. Also, this does not allow to use such abrasive tools until the abrasive-containing pellets are completely worn out and the whole quantity of the diamond grains is utilized.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide an abrasive-containing element, an abrasive tool with a plurality of abrasive-containing elements, and a method of manufacturing the same, which avoid the disadvantages of the prior art.

In keeping with these objects and with others which will become apparent herein after, one feature of the present invention resides briefly stated, in a abrasive-containing element having a pellet provided with an abrasive-containing layer and an abrasive-free layer, and at least one holding member having one end connected with the abrasive free-layer of the pellet and a shaft introducible into a tool body to connect the abrasive-containing element with the tool body.

When the abrasive-containing element is designed according to the present invention, it ensures a strong connection of the pellets to the tool body, thus allowing a high-pressure high-speed machining of parts with an abrasive tool equipped with such abrasive-containing elements, and at the same time it also ensures a long service life of the abrasive-containing elements till the abrasive-containing layers of their pellets are completely used.

According to a further feature of the present invention the holding member can have a head provided at its one end and embedded in the abrasive-free layer of the pellet, and the shaft can be threaded and screwable into the tool body.

According to a further feature of the present invention the head of the holding member embedded in the abrasive-free layer of the pellet can have a cross-section narrowing from the one end of the holding member towards the treaded shaft.

According to a further feature of the present invention the abrasive-containing element having a pellet provided with an abrasive-containing layer and an abrasive-free layer, has more than one holding member each having one end connected with the abrasive-free layer of the pellet and the shaft introducible into a tool body.

According to a further feature of the present invention, an abrasive tool is provided which contains a tool body and a plurality of abrasive-containing elements connected to the tool body and each having a pellet provided with an abrasive-containing layer and an abrasive-free layer and at least one holding member having one end connected with the abrasive-free layer of the pellet and a shaft introducible into the tool body.

According to a further feature of the present invention, a method of manufacturing a diamond tool is provided, which contains the steps of making a tool body, making a plurality of abrasive-containing elements and each having a pellet provided with an abrasive-containing layer and an abrasive-free layer and at least one holding member having one end connected with the abrasive-free layer of the pellet and a shaft, and the shaft of the holding member of each of the abrasive-containing elements is introduced into the tool body to connect the abrasive-containing elements with the tool body.

The present invention will be described in detail hereinbelow with the reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing a cross-section of an abrasive-containing element in accordance with the present invention;

FIGS. 2-4′ are views showing the abrasive-containing elements in accordance with further embodiments of the present invention;

FIGS. 5 and 6 are views showing a cross-section of two abrasive tools provided with the abrasive-containing elements on their concave and convex surfaces in accordance with two embodiments of the present invention;

FIG. 7 is a view showing a perspective view of a disc-shaped abrasive tool provided with the abrasive-containing elements on its flat axial side surface in accordance with another embodiment of the present invention;

FIG. 8 is a view showing a perspective view of a disc-shaped abrasive tool provided with the abrasive-containing elements on its circumferential surface in accordance with another embodiment of the present invention;

FIGS. 9 and 10 are an axial view and a cross-section of a disc-shaped abrasive tool provided with the abrasive-containing elements on its axial side surface in accordance with another embodiment of the present invention;

FIGS. 11 and 11′ are a perspective view an abrasive tool provided with the abrasive-containing elements on its curved circumferential surface and of an abrasive-containing element for it in accordance with another embodiment of the present invention; and

FIG. 12 is a view illustrating a method of producing abrasive-containing elements according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

An abrasive-containing element in accordance with one embodiment of the present invention is shown in FIG. 1 and identified with reference numeral 1. The abrasive-containing element 1 has a pellet 2 for machining of corresponding parts, and a holding member 3 for holding the abrasive-containing element 1 in an abrasive-tool body.

The pellet 2 is provided with an abrasive-containing layer 4 and an abrasive-free layer 5. The abrasive-containing layer 4 of the pellet 2 has a plurality of abrasive grains, for example diamond grains 6 embedded in a binder 7 which can be composed of metal, resin, or other materials.

The holding member 3 has a first end 8 connected with the abrasive-free layer 5 of the pellet 2 and another opposite end 9 with which it is insertable into a tool body, as well be explained in detail hereinbelow. The first end 8 preferably has a head portion 10 which narrows towards a shaft 11 of the holding member. The shaft 11 of the holding member 3 can be provided with a thread 12 so that it can be screwed into the tool body. The head portion 10 connects the pellet 2 of the abrasive-containing element 1 with the holding member 3.

The abrasive-containing element in accordance with another embodiment of the present invention is shown in FIG. 2 and is identified with reference numeral 1′. The abrasive-containing element 1′ has a pellet 2′ with a convex outer surface for machining of corresponding parts, and a holding member 3′ for holding the abrasive-containing element 1′ in an abrasive-tool body.

An abrasive-containing element in accordance with a further embodiment of the present invention is shown in FIG. 3 and is identified with reference numeral 1″. The abrasive-containing element 1″ has a pellet 2″ with a concave outer surface for machining of corresponding parts, and a holding member 3″ for holding the abrasive-containing element 1″ in an abrasive-tool body.

An abrasive-containing element in accordance with a further embodiment of the present invention is shown in FIG. 4 and is identified with reference numeral 1′″. The abrasive-containing element 1′″ has a single pellet 2′″ with an outer surface for machining of corresponding part, and two holding members 3′″ for holding the abrasive-containing element 1′″ in an abrasive-tool body. According to the present invention more than two holding members 3′″ can be provided in the single abrasive-containing element as well.

According to a very important feature of the present invention, the first end 8 with a part of the head portion 10 of the holding member 3, 3′, 3″,3′″ is arranged exclusively in the abrasive-free layer 5 of the pellet 2, 2′,2″,2′″ and does not extend into its abrasive-containing layer 4. As a result, the abrasive-containing element 1, 1′, 1″, 1′″ can be used for machining of a part until all abrasive grains in the whole volume of the abrasive-containing layer 4 are utilized. The holding member 3, 3′, 3′″, 3′″ thus not only ensures a strong connection of the pellet 2, 2′,2′″,2″″ to the tool body, thus allowing a high-pressure high-speed machining of parts with an abrasive tool equipped with such abrasive-containing elements, but it also ensures a long service life of the abrasive-containing elements till the abrasive-containing layer 4 of its pellets is completely used, and thus the longer service life of the abrasive tool as a whole.

FIG. 5 shows a cross-section of an abrasive tool 13 for machining convex surfaces. It has a tool body 14 having a concave surface and is provided with a plurality of the abrasive-containing elements 1 in accordance with the present invention. The abrasive-containing elements 1 have the pellets 2 attached to the concave surface of the tool body 14 by the holding members 3.

FIG. 6 shows a cross-section of a diamond tool 15 for machining concave surfaces. It has a tool body 16 having a convex surface and is provided with a plurality of the abrasive-containing elements 1 in accordance with the present invention. The abrasive-containing elements 1 have the pellets 2 attached to the convex surface of the tool body 16 by the holding members 3.

FIG. 7 shows an abrasive tool 17 for machining parts with its axial side face surface. It has a disc-shaped tool body 18 with the axial face surface provided with a plurality of the abrasive-containing elements 1 in accordance with the present invention. The abrasive-containing elements 1 have the pellets 2 attached to the axial side face surface of the tool body 18 by the holding members 3.

FIG. 8 is a view showing an abrasive tool 19 for machining parts with its circumferential surface. It has a disc-shaped tool body 20 with the circumferential surface provided with a plurality of the abrasive-containing elements 1 in accordance with the present invention. The abrasive-containing elements 1 have the pellets 2 attached to the circumferential surface of the tool body 18 by the holding members 3.

FIGS. 9 and 10 are views showing a further abrasive tool 21 for machining parts with its side face surface. It has a disc-shaped tool body 22 with the axial side face surface provided with a plurality of the abrasive-containing elements 1 in accordance with the present invention. The abrasive-containing elements 1 have the pellets 2 attached to the axial side face surface of the tool body 22 by the holding members 3.

FIGS. 11 and 11′ are views showing an abrasive tool 23 with a curved peripheral surface provided with the abrasive-containing elements 1. It has a tool body 24 having a concave peripheral surface provided with a plurality of the curved abrasive-containing elements 1 in accordance with the present invention, spaced from one another in a circumferential direction. The abrasive-containing elements 1 have the pellets 2 attached to the tool body 24 by the holding members 3.

FIG. 12 illustrates a method for producing abrasive-containing elements according to the present invention. A mold is utilized which includes mold parts 13, 13′ and 13″.

A holding member 3 is introduced into the mold, as well as mixtures with compositions to make an abrasive-free layer 5 and an abrasive-containing layer 4 into a thusly formed mold cavity. Then an upper mold part 14, or 14′, or 14″, depending on a desired shape of the abrasive-containing elements, is introduced into the opposite end of the mold. Under the action of correspondingly selected pressure and temperature, an abrasive-containing element according to the present invention is thusly produced. An abrasive-containing tool is produced by introducing a plurality of the thusly made abrasive-containing elements into a body of the tool with the use the their holding members.

The present invention is not limited to the details shown since various modifications and structural changes are possible without departing from the spirit of the present invention. 

What is desired to be protected by Letters Patent is set in particular in the appended claims: 1.-6. (canceled)
 7. An abrasive tool, comprising a tool body having an outer surface adapted to face an object to be machined; and a plurality of abrasive-containing elements inserted into the tool body and each having an abrasive-containing layer and an abrasive-free layer, and at least one holding member having one end introduced in the abrasive-free layer and another opposite end introduced in the tool body to connect the abrasive-containing elements with the tool body, wherein the abrasive-free layer of each of the abrasive-containing elements is introduced into the tool body, while the abrasive-containing layer of each of the abrasive-containing elements projects outwardly of the outer surface of the tool body and is located completely outside of the tool body, wherein each of said abrasive-containing elements has an outer working surface of a curvilinear shape, wherein said one end of said at least one holding member has a surface which faces said outer working surface of each of said abrasive-containing elements and has a curvilinear shape substantially corresponding to the curvilinear shape of said outer working surface of each of said abrasive-containing elements.
 8. An abrasive tool of claim 7, wherein the abrasive-free layer of each of the abrasive-containing elements has a surface which faces the abrasive-containing layer and is coplanar with the outer surface of the tool body.
 9. An abrasive tool of claim 7, wherein the abrasive-free layer of each of the abrasive containing elements has a surface which faces the abrasive-containing layer and is located outwardly of the tool body at a distance from the outer surface of the tool body.
 10. An abrasive tool of claim 7, wherein at least some of the abrasive-containing elements have each more than one holding member and each of the holding members has one end connected with the abrasive-free layer and another opposite end introducible into the tool body.
 11. A method of manufacturing an abrasive tool, comprising the steps of providing a tool body having an outer surface adapted to face an object to be machined; providing a plurality of abrasive-containing elements inserted into the tool body and each having an abrasive-containing layer and an abrasive-free layer, and at least one holding member having one end introduced in the abrasive-free layer and another opposite end introduced in the tool body to connect the abrasive-containing elements with the tool body; and introducing the abrasive-free layer of each of the abrasive-containing elements into the tool body, so that the abrasive-containing layer of each of the abrasive-containing elements projects outwardly of the outer surface of the tool body and is located completely outside of the tool body forming each of said abrasive-containing elements with an outer working surface of a curvilinear shape, forming said one end of said at least one holding member with a surface which faces said outer working surface of each abrasive-containing elements and has a curvilinear shape substantially corresponding to the curvilinear shape of said outer working surface of each of said abrasive-containing elements.
 12. A method of manufacturing an abrasive tool of claim 11, further comprising arranging the abrasive-free layer of each of the abrasive-containing elements so that its surface which faces the abrasive-containing layer is coplanar with the outer surface of the tool body.
 13. A method of manufacturing an abrasive tool of claim 11, further comprising arranging the abrasive-free layer of each of the abrasive containing elements so that its surface which faces the abrasive-containing layer is located outwardly of the tool body at a distance from the outer surface of the tool body.
 14. A method of manufacturing an abrasive tool of claim 11, further comprising providing at least some of the abrasive-containing elements each with more than one holding member so that each of the holding members has one end connected with the abrasive-free layer and another opposite end introducible into the tool body.
 15. An abrasive tool of claim 7, wherein the curvilinear shape of said outer working surface of each of said abrasive-containing elements and the corresponding curvilinear shape of said end of said holding member are selected from the group consisting of a convex shape and a concave shape.
 16. A method of manufacturing an abrasive tool of claim 11, and further comprising forming the curvilinear shape of said outer working surface of each of said abrasive-containing elements and the corresponding curvilinear shape of said end of said holding member as a shape selected from the group consisting of a convex shape and a concave shape. 